Dementia with Lewy bodies (DLB) is thought to be the second commonest cause of neurodegenerative dementia in older people, accounting 15 to 25% cases at autopsy. However, to date there are no reliable methods of instrumental and laboratory diagnosis of this disease while its treatment is based on reducing the symptoms. The drug X has been shown to have neuroprotective effects in neurodegenerative diseases. Therefore, we aimed to clarify the medicinal effectiveness of drug X through manganese-enhanced magnetic resonance imaging (MEMRI). Our results indicated that drug X may have clinical potential in the treatment of DLB.